Alarm / Immobiliser Question- Help!

[wattfield]

I have a problem with the immobiliser on my 1994 rav4. The Battery went flat, (my fault, left the lights on...), and it wouldn't unlock using the button on the fob. So I opened the door the old fashioned way with the key, so the car has been immobilised. I've tried connecting a booster to the Battery, but still the keyfob doesn't turn off the immobiliser or unlock the doors. There's a "keyhole" for want of a better term, on the alarm unit, which I think may be to reset the alarm, but I don't have a key.

Questions:

Can I buy a key to reset?

Is there another way of doing it?

If I disconnect the alarm, will it start? (so at least I can get to work in the morning!)

I don't know if the alarm is original, as there's no mention of it in my owners handbook, but it is a Toyota alarm (the keyfob is rectangular with a black and a red button and a slide on the side). It may have been fitted later? It connects by a multiplug into the loom.

Can anyone help? Bothwell buyer perhaps? (By the way, It broke a few short miles from your neck of the woods at my parent's house!)

[wattfield]

The recovery guy who rescued me reckoned I'd either have to get an alarm reset key or have an autoelectrician take the thing apart.

I've just charged up the Battery, put it back in, and everything works!

So how come the recovery guy's booster pack didn't work? And who cares???

[hedleyf]

HI,

These are port of entry fitted when the car was new, its a scorpion made system, the problem with these are as they get to this age and the Battery goes flat as in your case they seem to trip out never to go again, you can not buy a remote seperatly as they came matched with the alarm ecu and now that scorpion are no longer you only have one option and that is to remove it, the job can be done by your toyota dealer or a car spark either way It should not cost you more than one and a half hours of labour,hope this is of some help.

Hedley,

[bothwell_buyer]

I had the same system until the garage lost the remining fob and ripped out the ecu and wiring for the immobiliser. I still have the wee key for the box - dunno if it would fit yours but your welcome to try it - pm with an address.

As far as the system - ye it goes bonkers when the Battery is disconnected or goes flat. I think by standing with the fob next to the door, and holding black button, it was possible to re-tune thing assuming fob Battery is ok as well.

Do you have the instructions for this sytem? If not, I still have mine. I'll look them out in the morning when I don't wake up the whole house!

[hedleyf]

Hi chaps,

Seems to be some confusion as to what that small key does, they are different to each other but do repeat the code every so often a bit like locking wheel nut keys ,this small key will only turn off the siren and nothing else,your problem will still exsist but at least you would not have the noise.

Hedley,

[bothwell_buyer]

Hi chaps,

Seems to be some confusion as to what that small key does, they are different to each other but do repeat the code every so often a bit like locking wheel nut keys ,this small key will only turn off the siren and nothing else,your problem will still exsist but at least you would not have the noise.

Hedley,

Ye - the fob still needs to reset itself to the alarm box or vice versa

[tonybony]

I've had the same problem with an Nreg Rav4, the Battery went flat, now the fob will not deactivate the alarm and immobiliser. At least the key turns off the siren. I've spoken to Toyota and was told to try pressing the black fob button for 15 secs until the light goes out at which point it should have retuned to the alarm ECU. He also stated if it didn't work just repeat the process as it can take several goes. I did this 20 times with no joy (sob), so again rang toyota and was told that if you put the ignition key in and turn it to third click position, then after 30secs it should recognise you as the owner and allow the car to start, this just allows you to drive it to the garage and isn't a fix, unless you are happy to do this every day. Unfortunately that hasn't worked for me either. I may just hire a sparky to remove the whole thing unless anyone knows how to get the fob to sych with the alarm.

:(

HI,

These are port of entry fitted when the car was new, its a scorpion made system, the problem with these are as they get to this age and the battery goes flat as in your case they seem to trip out never to go again, you can not buy a remote seperatly as they came matched with the alarm ecu and now that scorpion are no longer you only have one option and that is to remove it, the job can be done by your toyota dealer or a car spark either way It should not cost you more than one and a half hours of labour,hope this is of some help.

Hedley,

[bothwell_buyer]

Hi - another member from anchormanland!!!

Ye - sounds like you've done everything to make it work. Mind the electronic wizardry will have been designed almost 20 years ago - before LCD TVs and not long after valves became obsolete.

Get yourself an up to date immobiliser if yer worried. The lecky should leave the central locking all working (case he/she gets carried away). One easy method of immobilising it is to the earth of the the ecu and place a hidden switch somewhere - costs next to nothing. You could even activate it with a remote control and relay. You won't get the beep beep etc.

[tonybony]

RAV4 1995 Scorpion T5000 Alarm unit T918 removal.

1. Located the Alarm unit 918T (grey box with an S on it) under the dash, possible behind the glovebox.

2. Remove 3 retaining tie raps holding three side entry plugs.

3. Remove the 15 way plug.

4. Cut from pin 12 Violet and pin 13 Red/Yellow wires.

5. Remove enough insulation to twist and short together.

6. Test that the motor now starts.

7. Remove remaining plugs from this unit and discard.

8. The above method will render the Central door lock fob inoperative.

9. Note: - On the 15 way plug pins 6; 9; 14 and 15 are blank.

10. Make sure the twisted pair joint is secure, i.e. won’t come apart.

11. This leaves the toyota immobiliser still working as its a seperate unit. The key fob is scorpion and therefore will no longer work as the unit is removed.

Hi chaps,

Seems to be some confusion as to what that small key does, they are different to each other but do repeat the code every so often a bit like locking wheel nut keys ,this small key will only turn off the siren and nothing else,your problem will still exsist but at least you would not have the noise.

Hedley,

Ye - the fob still needs to reset itself to the alarm box or vice versa

[shersh]

. I had the same problem on my 1995 Rav4 a couple of years ago. The alarm unit is an early Scorpian and is housed behenind the glove box. The immobiliser unit is also Scorpian and is housed by the passenger door in the footwell. The immobiliser interupted two circuits on mine. Two pairs of black wires from the immobiliser come across from the passengers side of the dashboard to the drivers side and intrerupt two wires in the original loom. These black wires are obvious because they are not part of the original loom. All you need to do is rejoin the original wires that the black wiresconnect to and tie back the black wires and tape them off. You now have put the car back to the original state prior to the immobiliser being installed and your car should start.

Alternatively I have a spare Scorpian alarm unit with one key fob up for grabs. With this it should be a case of swopping the alarm unit which just plugs in.

[bothwell_buyer]

. I had the same problem on my 1995 Rav4 a couple of years ago. The alarm unit is an early Scorpian and is housed behenind the glove box. The immobiliser unit is also Scorpian and is housed by the passenger door in the footwell. The immobiliser interupted two circuits on mine. Two pairs of black wires from the immobiliser come across from the passengers side of the dashboard to the drivers side and intrerupt two wires in the original loom. These black wires are obvious because they are not part of the original loom. All you need to do is rejoin the original wires that the black wiresconnect to and tie back the black wires and tape them off. You now have put the car back to the original state prior to the immobiliser being installed and your car should start.

Alternatively I have a spare Scorpian alarm unit with one key fob up for grabs. With this it should be a case of swopping the alarm unit which just plugs in.

I've found the siren (still fitted) which anyone is welcome to!!

[Mick-s]

. I had the same problem on my 1995 Rav4 a couple of years ago. The alarm unit is an early Scorpian and is housed behenind the glove box. The immobiliser unit is also Scorpian and is housed by the passenger door in the footwell. The immobiliser interupted two circuits on mine. Two pairs of black wires from the immobiliser come across from the passengers side of the dashboard to the drivers side and intrerupt two wires in the original loom. These black wires are obvious because they are not part of the original loom. All you need to do is rejoin the original wires that the black wiresconnect to and tie back the black wires and tape them off. You now have put the car back to the original state prior to the immobiliser being installed and your car should start.

Alternatively I have a spare Scorpian alarm unit with one key fob up for grabs. With this it should be a case of swopping the alarm unit which just plugs in.

Do you still have the scorpion alarm?

[bothwell_buyer]

. I had the same problem on my 1995 Rav4 a couple of years ago. The alarm unit is an early Scorpian and is housed behenind the glove box. The immobiliser unit is also Scorpian and is housed by the passenger door in the footwell. The immobiliser interupted two circuits on mine. Two pairs of black wires from the immobiliser come across from the passengers side of the dashboard to the drivers side and intrerupt two wires in the original loom. These black wires are obvious because they are not part of the original loom. All you need to do is rejoin the original wires that the black wiresconnect to and tie back the black wires and tape them off. You now have put the car back to the original state prior to the immobiliser being installed and your car should start.

Alternatively I have a spare Scorpian alarm unit with one key fob up for grabs. With this it should be a case of swopping the alarm unit which just plugs in.

Do you still have the scorpion alarm?

I have it - in bits! No fob though.

[geomowat]

On 29 April 2008 at 10:56 PM, tonybony said:

RAV4 1995 Scorpion T5000 Alarm unit T918 removal.

1. Located the Alarm unit 918T (grey box with an S on it) under the dash, possible behind the glovebox.

2. Remove 3 retaining tie raps holding three side entry plugs.

3. Remove the 15 way plug.

4. Cut from pin 12 Violet and pin 13 Red/Yellow wires.

5. Remove enough insulation to twist and short together.

6. Test that the motor now starts.

7. Remove remaining plugs from this unit and discard.

8. The above method will render the Central door lock fob inoperative.

9. Note: - On the 15 way plug pins 6; 9; 14 and 15 are blank.

10. Make sure the twisted pair joint is secure, i.e. won’t come apart.

11. This leaves the toyota immobiliser still working as its a seperate unit. The key fob is scorpion and therefore will no longer work as the unit is removed.

My problem was that after I changed the car Battery, the car would not start and the four indicators flashed for about 30 secs. then stopped. If I tried to restart again, then the clicking (which comes from the 918T box that has Toyota P.N. 00270-01099-EX  FEGG on it) starts again. I have tried the key fob which does not  unlock the central locking (which was getting a bit dodgy anyway) and the holding down the black button and the 'third click of the key' routine mentioned elsewhere on this thread. When trying to start it, there is a dull hum coming from somewhere behind the passenger dash, but no attempt to operate the starter motor.

My questions then are:

1 Is it possible to get the key fob to reprogramme itself other than just holding down the black button?

2 If I rewire to bypass the 918T box, what else does not work?

3 Point 11 above says the the Toyota immobiliser still works as a separate unit and I cannot follow this as the description suggests that this box is entirely removed — what have I not understood?

Thanks in advance,

George

 

[Nigel watson]

My Battery was flat so I'm jump starting my 2002Rav 4 that way. The indicator lights are permanently on but the dashboard lights and gauges don't come on ...yet.. the car engine turns over but won't start . What is occurring please 

[Avalon]

On 9/13/2022 at 10:38 AM, Nigel watson said:

My battery was flat so I'm jump starting my 2002Rav 4 that way. The indicator lights are permanently on but the dashboard lights and gauges don't come on ...yet.. the car engine turns over but won't start . What is occurring please 

A 2002 is likely a MK2, the posts above relate to a MK1. Assuming you're providing enough power, the gauges should operate - are you using a jump pack or another car? If the former, ensure it's properly charged, if the latter, make sure it's running before trying to jump start it. The engine won't catch if the key isn't coded to the car's ECU/Immobiliser, presumably this is a known good key?